GARDAI have made significant progress with their inquiries into the double murder in the centre of Dublin last Sunday.
They have gathered new information, which they believe could be vital to building up their case against the killers, the Irish Independent has learned.
Senior officers said last night they were satisfied with the investigation so far although a number of lines of inquiry had yet to be completed.
Local gardai are being backed up by detectives from the organised crime unit in the investigation into the fatal shootings of Brendan Molyneaux (45) and Paddy Mooney (58) in the Pearse House flats complex in Pearse Street.
Detectives are continuing to question the prime suspect for the shootings, his girlfriend and another man, who were all arrested in Finglas and the city centre less than two hours after the murders.
Officers are awaiting the results of forensic tests on items taken from the murder scene in Mr Mooney's flat and these could yield vital clues to the identity of the gunman and his accomplice.
Gardai will also have to decide this evening whether to go to another special sitting of Dublin District Court to seek a further extension of the detention period for the three suspects.
Members of the garda water unit carried out a search of the Royal Canal yesterday, close to Spencer Dock, in a bid to find the gun used in the killings.
Based on an examination of the information gathered so far, senior officers ordered a search of the frozen canal, but the weapon was not found.
The suspected gunman is well known to gardai and from Finglas. He has already been linked to at least one other gangland murder in Dublin in the past two years and has been described as a "gun for hire".
Gardai are separately building up a file on the gang boss, who is believed to have been involved with two of his associates in organising Sunday's attack.
Meanwhile, heavily armed members of the emergency response unit were sent on to the streets of Dublin's trouble spots last night in a drive against organised crime gangs.
The special unit has been tasked with carrying out "search and disruption" tactics against suspected gangland figures.
Armed detectives set up checkpoints in areas such as Ballymun and Coolock and also in Finglas and Blanchardstown.
Senior garda officers said the city-wide operation would continue for several weeks.